Role of platelet indices in diagnosing myeloproliferative neoplasms and their utility in differentiation from reactive thrombocytosis

Objectives: Automated hematology analyzers provide platelet indices as part of a routine complete blood count. These include mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT), and platelet large cell ratio (P-LCR). The present study aimed to investigate the diagnostic utility of platelet indices in thrombocytosis, to determine their value in distinguishing myeloproliferative neoplasms (MPNs) from reactive thrombocytosis (RT), and evaluating their potential role in the sub-classification of MPNs. Material and Methods: This retrospective study included 105 MPN cases, 125 RT cases, and 125 controls. Retrospective data were analyzed using platelet count, MPV, PCT, PDW, and P-LCR values obtained from the Sysmex XN1000 analyzer. Results: Chronic myeloid leukemia (CML) was the most common MPN in the study. PCT showed the highest discriminative ability between MPN and normal controls, with higher mean values in MPN. MPV, PDW, and P-LCR were significantly higher in MPNs compared to RT, while PCT and platelet counts were highest in RT and proved to be strong predictors for differentiating MPN from RT. Within the MPN subtypes, MPV was highest in CML, followed by essential thrombocythemia (ET) and polycythemia vera (PV). P-LCR was highest in CML, followed by PV and ET. Receiver operating characteristic and logistic regression confirmed the strong predictive performance of these indices. Conclusion: Platelet indices are readily available through routine hemogram reports at no additional cost. These indices are cost-effective, non-invasive tools to aid early differentiation of MPNs from RT, and can potentially guide timely decisions regarding bone marrow examination and further molecular testing.